From Raw Materials to the Silver Screen

When the lights go down at the theater and the movie starts up, you’re witnessing something kind of magical  — movement caught on film by light and chemistry. Props to George Eastman for figuring that one out in the 1880s. To get the full picture of how motion-picture film is made and how it works, we have to start at the beginning. After Eastman invented photographic film, he patented his first roll-film camera and registered the trademark for Kodak in 1888. Flash-forward a little and we find ourselves in 1899, when he marketed the first commercial transparent roll film, which enabled Thomas Edison to develop the first motion-picture camera. Since then, Kodak has earned nine Oscar statuettes — more than any other non-studio company — for its technical contributions to the movie industry. A pretty big deal. And you might be wondering just how this film is created and how it works, and how Kodak ended up with all those Oscars. We’re glad you asked.

How Kodak Makes Film

It all starts in Rochester, New York — the same factory Kodak has called home since 1890. Despite the digital revolution, the plant is still humming, running (mostly in the dark) 24 hours a day, seven days a week, and is the only large-scale manufacturer of color motion-picture film in the world, and the sole supplier of 65mm motion-picture film worldwide. 

The process breaks down into three big stages that are the same for still and motion-picture film: making the base and sensitizing, emulsion and coating, and finishing it into rolls. The basic recipe for motion-picture film is also the same one Kodak uses for still photography — silver halide crystals, gelatin, and a flexible plastic base. 

But despite these similarities, motion-picture camera film (for capture) and print films (for projection) are different animals. Motion-picture camera films are built to be transported at high speed through a movie camera, and print films are built to endure the mechanical chaos of running through a projector, showing after showing on a theater screen. Everything about the manufacturing process is tuned for that. Let’s get into it.

Stage 1: Building the Base

Motion-picture camera negative is traditionally built on a cellulose triacetate base — acetate, not the polyester base used for most still films. Acetate can be cement-spliced, which matters when editors need to physically cut and rejoin the film during post-production. The acetate is made by dissolving cellulose triacetate pellets, solvents, and a plasticizer into a thick liquid called a dope, which is cast onto a slowly rotating drum and allowed to dry into a thin, flexible, clear strip. The continuous ribbon of transparent plastic is wound into enormous rolls that will eventually be coated with light-sensitive chemistry.

The rolls of base material coming out of this stage are massive — thousands of feet long and wider than the final film format, ready to be slit down later.

Stage 2: The Emulsion & Coating 

This is where the magic happens. And where most of the work takes place in total darkness. This might feel like a chemistry lesson, and well, it’s because it sort of is. Science is for the creatives, too. Once the various components of a particular film are prepared, created and weighed out for a film coating event (there are hundreds) then the coating operations begin.

Now we enter the melting room, where machines called dumpers move silver halide emulsions and other chemical compounds into large kettles. A row of 26 coating stations where large kettles with mixers re-melt the gelatin containing components and blend the disparate compounds in preparation to coat film. This room is kept in total darkness when mixing is underway.

These individual melts need to be filtered to remove any possible materials that might disrupt the film coatings that are ultimately tens of microns thick (much less than the width of a human hair). Melts are transferred to the coating machine through a combination of processes where the liquid emulsion passes through filters to catch any undissolved gelatin or foreign matter, and ultrasonic vibrations shake out air bubbles that could leave voids in the finished film all maintained at a constant temperature of above 100°F. The whole thing has to happen with zero vibration and absolutely stable temperature, because any variation will affect the uniformity of the coating and, ultimately, the look of the film.

After coating, samples are taken for testing of physical and sensitometry properties to make sure that all went swimmingly. From there the film master roll is transferred to light-tight transport caskets.

Stage 3: Finishing

Once coated, dried, and tested, the enormous rolls of sensitized film move to the finishing department — still under tightly controlled conditions. Here the film is slit to its final width: 16mm, 35mm, 65mm, and 70mm for large format projection, with Super 8 for smaller-gauge work. The film is then perforated, because the entire mechanical system of a motion-picture camera and projector depends on those perforations to move the film frame by frame. The perforation pitch, size, and placement are standardized to thousandths of an inch.

Then come the edge codes, aka the KeyKode: identifying numbers, film stock codes, and footage markers that are printed along the border of the film. These allow editors to trace any frame back to its exact position on the original camera negative.

The finished film is wound into spools of various lengths depending on the application, sealed in light-tight cans, and shipped to productions around the world. A single 1,000-foot roll of 35mm film at 24 frames per second holds roughly 11 minutes of footage. A feature film can burn through a dozen rolls in a single day of shooting. 

And the Oscar goes to… 

Even though a lot of things today happen digitally, there are still directors that chose to use celluloid to capture their films. And Kodak currently holds the record for the most Oscars as a non-studio company for their engineering and technological breakthroughs in motion-picture film. Wondering what movies have been shot on Kodak film and have won some of those little gold statuettes at the most recent Oscars? 

One Battle After Another

• This one cleaned up at the Oscars, with six awards, including Best Picture and Best Film Editing. 
• Format: 35mm
• Palette: Kodak Vision3 500T Color Negative Film 5219, Kodak Vision3 250D Color Negative Film 5207, and Kodak Vision3 200T Color Negative Film 5213

Sentimental Value

• Took home Best International Feature Film 
• Format: 35mm
• Palette: Kodak Vision3 250D Color Negative Film 5207, Kodak Vision3 500T Color Negative Film 5219, and Kodak Vision3 50D 5203

Sinners

• Amongst other awards, it won Best Cinematography and made history: Autumn Durald Arkapaw was the first female to win this award, and she is the first female to ever shoot a full-length film on 65mm in IMAX format. 
• Format: 65mm
• Palette: Kodak Vision3 500T Color Negative Film 5219

And only time will tell how films like Christopher Nolan’s The Odyssey and Steven Spielberg's Disclosure Day, which were also shot on Kodak film, will perform at the Oscars. Might be the fourth year in a row that movies shot on film win Best Picture and Best Cinematography. 

Learn more at kodak.com/go/film

All photos courtesy of Team 2 Films, Leon Barnard